title: Severe hypoglycemia and cognitive decline in older people with type 2 diabetes: the Edinburgh type 2 diabetes study.
abstract: OBJECTIVE
  People with type 2 diabetes are at increased risk of age-related cognitive decline and dementia. Hypoglycemia is a candidate risk factor, but the direction of association between episodes of severe hypoglycemia and cognitive decline in type 2 diabetes remains uncertain.
  
  
  METHODS
  In the Edinburgh Type 2 Diabetes Study, cognitive function was assessed in 831 adults with type 2 diabetes (aged 60-75 years) at baseline and after 4 years. Scores on seven neuropsychological tests were combined into a standardized general ability factor g. Self-reported history of severe hypoglycemia at baseline (history of hypoglycemia) and at follow-up (incident hypoglycemia) was recorded.
  
  
  RESULTS
  A history of hypoglycemia was reported by 9.3% of subjects, and 10.2% reported incident hypoglycemia. Incident hypoglycemia was associated with poorer cognitive ability at baseline (age- and sex-adjusted odds ratio for lowest tertile of g 2.04 [95% CI 1.25-3.31], P = 0.004). Both history of hypoglycemia and incident hypoglycemia were also associated with greater cognitive decline during follow-up (mean follow-up g adjusted for age, sex, and baseline g -0.25 vs. 0.03 [P = 0.02] and -0.28 vs. 0.04 [P = 0.01], respectively), including after addition of vascular risk factors and cardiovascular and microvascular disease to the models (-0.23 vs. 0.03 [P = 0.04] and -0.21 vs. 0.05 [P = 0.03], respectively).
  
  
  CONCLUSIONS
  The relationship between cognitive impairment and hypoglycemia appeared complex, with severe hypoglycemia associated with both poorer initial cognitive ability and accelerated cognitive decline.
authors.affiliation: Corresponding authors: Insa Feinkohl, i.feinkohl@sms.ed.ac.uk.
authors.forename: Insa
authors.initials: I
authors.lastname: Feinkohl
authors.forename: Phyu Phyu
authors.initials: PP
authors.lastname: Aung
authors.forename: Marketa
authors.initials: M
authors.lastname: Keller
authors.forename: Christine M
authors.initials: CM
authors.lastname: Robertson
authors.forename: Joanne R
authors.initials: JR
authors.lastname: Morling
authors.forename: Stela
authors.initials: S
authors.lastname: McLachlan
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Deary
authors.forename: Brian M
authors.initials: BM
authors.lastname: Frier
authors.forename: Mark W J
authors.initials: MW
authors.lastname: Strachan
authors.forename: Jackie F
authors.initials: JF
authors.lastname: Price
mesh_terms: D000368:Aged; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications / Q000523:psychology*; D005260:Female; D006801:Humans; D007003:Hypoglycemia / Q000150:complications*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests